Valved bag having side gussets and made from plastics material sheeting



Aprl 29, 1969 F. F. BROCKMULLER VALVED BAG HAVING SIDE GUSSETS AND MADE FROM PLASTICS MATERIAL SHEETING Sheet Filed Sept. 22, 1967 ;NW u a April '29, 1969 F. F. 'ROCKMULLER 344ll99 VALVED BAG' HAVING SIDE GUSSETS AND MADE FROM PLASTICS MATERIAL SHEETING Z of 2 Sheet Filed Sept. 22, 1967 /NVENTOR Fmaomcn rewz smmiusa HTTOR/ EyS United States Patent O VALVED BAG HAVING SIDE GUSSETS AND MADE FROM PLASTICS MATERIAL SHEETING Friedrich Franz Brockmuller, Lengerich, Westphalia, Germany, assignor to Windmoller & Holscher Filed Sept. 22, 1967, Ser. No. 669,949 Claims priority, application Germany, Oct. 3, 1966,

Int. c. B65d 31/1'4,33/18, 77/14 U.S. Cl. 229-625 4 Claims ABSTRACT OF THE DISCLOSURE Valved bags having side gussets and made from singleply plastics material sheeting have .already been proposed, in which one bag wall is longer than the other adjacent to each bag end and is reversely folded about and adhered to the shorter wall when the single-ply web has been transformed into a tubing 'by a reverse folding of the side portions and the formation of an adhered longitudinal seam before the individual tube sections were severed. In these bags, the valve consists of a tube of plastics material, which lies in the longitudinal seam and has a top fold line extending to the fold line of the flap which forms the end closure.

Owing to the difierence between the lengths of the forward and rear walls of the bag adjacent to each end thereof, transverse lines of weakness must be provided before the tubing is formed. These lines of weakness must be designed in such a manner that their portions appearing on the top and bottom faces of the subsequently formed tubing are longitudinally spaced and are connected by oblique connecting lines disposed in the areas where the side gussets are subsequently formed. Such transverse lines of weakness are usually formed with the aid of perforating knives. When the tubing has been formed, the individual tube sections are torn from the tubing by tearof rolls and the Valved bags are formed by a reverse folding of the fiaps at the open ends.

On the other hand, plastics material sheeting is known which cannot be severed by being torn along transverse perforation lines, because the material is so tough that the lands of material between the openings pierced by the perforating knives cannot be torn off between the tear-oli rolls without a distortion of the material. This applies, e.g., to a known sheeting in which two very thin layers, which have been stretched or oriented at an angle of preferably 45 to their longitudinal direction, .are superimposed with crossing directions of orientation and bonded together. It is an object of the invention to provide a simple Valved bag which has side gussets and which can be made even from sheeting that cannot be severed by tearing oif individual tube sections along transverse perforation lines but must be severed by straight shear cuts. Besides, it is an object of the invention to provide a bag which distinguishes by a particularly simple manufacture.

According to the invention, a Valved bag is proposed which has side gussets and is made from a single-layer plastics material sheeting, which has been closed by an adhered longitudinal seam to form a tubing, which bag is provided with a tubular valve disposed in the adhered longitudinal seam close to one end of the bag. This bag is characterized in that a cover patch is adhered to one wall of the bag at each end thereof and is reversely folded together with the edge portions of the tubing about a fold line which is somewhat below the aligned, straightlined edges of the tube section end and said patch is adhered to the other wall of the bag. In a particularly desrable development of the invention, the cover patches may have the same width as the side gussets pulled open so that the cover patches .afford in the filled bag an additonal protection to the ends and stiffen the ends so as to promote the assumption of a blocklike shape by the bags when the latter are stacked and placed on pallets.

The invention will be explained more fully in the subsequent description with reference to the drawing, in which the process of -manufacturing the side-gusseted bag according to the invention and said bag itself are illustrated.

In the drawing:

FIG. 1 is a top plan view showing 'an open sheeting web with valves attached to it,

FIG. 2 a side elevaton showing the sheeting web of FIG. 1,

FIG. 3 a finished tube section with adhered end cover patches before the closing of the ends,

FIG. 4 a sectional View taken through the tube section on line IV-IV of FIG. 3 and FIG. 5 a finished, filled bag.

As is apparent from FIG. 1, a flat sheeting web 1 is provided with an adhesive band 9 beside one edge on the upper side and with an adhesive band 10 beside the other edge on the underside In a known tube-forming device, the -web is then formed with side gussets along lines 3, 4, 5 and 6, 7, 8 and is tr-ansformed in-to a tubing. In this operation, the two adhesive bands 9, 10 are joined to form the adhered longitudinal seam of the tubing. By a cutting mechanism, the tubing is then divided into tube sections by shear cuts along straight lines 2, which extend transversely to the direction of the web and are spaced predetermined distances apart.

Before the tubing is formed, valves 11 in the form of valve tubes made in known manner are applied to the open sheeting. The valve tubes may have a reinforcement 12 at the outwardly facing end. This reinforcement is formed in known manner by the application of a reinforcing strip or by `a reverse folding of one valve tube end portion.

The valve tubes are adhered to the web 1 at their reinforced end by means of the adhesive band 9 in such a manner that each valve tube is a predetermined distance apart from the subsequent line of cut 2. The upper edges of the valve tubes -are suitably approximately aligned with the fold line 19, which is to be provided in the form'ation of the bottom.

The side-gusseted tubing is divided along lines 2 extending transversely to the direction of travel by a straight cutting mechanism so that the tube section edges 13 and 13' (FIG. 3) are formed. According to the invention, cover patches 14 and 15 are secured by adhesive coatngs 16 (FIG. 4) at both tube section ends in the next operation.

The length of the cover patches is at least as large as the distance between the tubing edges 3', 6' and 4', 7'. The width of the cover patches is suitably at least as large as twice the depth of the side gussets, i.e., as large as the distance between lines 3, 4 and 6, 7. The center line of the cover patches is desirably in registry with the fold lines 19 and 20, along which the tube section ends are folded to close the bag ends when the adhesive bands 17 and 18 have been applied to the wall of the tubing section and the protruding ends of the cover patches.

As is apparent from FIGS. 3 and 4, the two cover patches 14 and 15 are applied to the same wall of the bag so that the application of the adhesve coatings 17,

18 at the two bag ends and the reverse folding along lines 19, 20 can be erfected in the closing machine from the same side at both tube section ends. As a result, the structural expenditure in the machine is much reduced.

If the application of adhesive to one face in the form of the adhesive band is sufficient for the formation of the adhered longitudinal seam of the tubing, the adhesve band 9 may be interrupted and may be provided only where it is required for securng the valve 11. For an adhering of the tucked-in side gussets to the respective cover patch and to that bag wall to which the flap is to be adhered, it is desirable to form the open web with punched holes 21 having centers which coincide with the subsequent line of cut 2 so that one half 22 of the holes 21 is at the leading edge of the tube section and the other half 23 is at the trailing edge of the tube section.

The adhesve coatings 16, 17 and 18 contact the tucked in side" gussets through the indentations 22 and 23 so that thevgussets adhere at the indentations to the cover patches 14 and 15 and, when the tube section ends have 1. A gusseted valve bag made from a single-layer plastic material sheeting and closed by an adhered longitudinal seam to form a tubing comprising front and back walls, said tubing further comprising straight cut and coterminous top end and bottom end edges, a tubular valve disposed in said longitudinal seam near to said top end edge, and a cover patch adhered to one of said walls of the tubing at the top and bottom ends thereof, wherein said top and bottom ends each are folded down upon themselves about a fold line spaced from said top and bottom ends of the tubing, respectively, and adhered to said tubing, the folcl line at said top end being flush with the upper edge of said tubular valve, said upper edge of the valve being closed, and wherein each said cover patch is also folded down about said fold line and adhered to the other of said walls of the tubing.

2. A gusseted valve bag according to claim 1, wherein said tubular valve is closed at its npper edge by a fold.

3. A valved bag having side gussets according to claim 1, characterized in that the cover patches have the same width as the side gussets when pulled open.

4. A valved bag having side gussets according to claim 1, characterzed in that the tube section ends are provided on the forward and/ or rear wall of the bag with apertures beside the outer edges of the side gusset and said apertures enable an adhering of the edges of the tube section adjacent to the side gussets to the cover patches and the bag wall to which the flap is adhered.

References Cited UNITED STATES PATENTS 3,22l,789 12/1965 Harding 229-625 3,243,099 3/1966 Winegard 229-62 DAVID M. BOCKENEK, Pr'mary Examner.

U.S. Cl. X.R. --9 

